## Si4 planar*

 Si3 / | Si1 - Si2 \ | Si4
Tell me about the atomic charges, dipole moment, bond lengths, angles, bond orders,
molecular orbital energies, or total energy.
Tell me about the best Lewis structure.

## Atomic Charges and Dipole Moment

SI1 charge= 0.056
SI2 charge= 0.055
SI3 charge=-0.055
SI4 charge=-0.055
with a dipole moment of 0.00058 Debye

## Bond Lengths:

between SI1 and SI2: distance=2.439 ang___ between SI1 and SI3: distance=2.350 ang___
between SI1 and SI4: distance=2.350 ang___ between SI2 and SI3: distance=2.350 ang___
between SI2 and SI4: distance=2.350 ang___ between SI3 and SI4: distance=4.017 ang___

## Bond Angles:

for SI3-SI1-SI2: angle=58.74 deg___ for SI4-SI1-SI2: angle=58.73 deg___

## Bond Orders (Mulliken):

between SI1 and SI2: order=1.125___ between SI1 and SI3: order=1.080___
between SI1 and SI4: order=1.080___ between SI2 and SI3: order=1.080___
between SI2 and SI4: order=1.080___ between SI3 and SI4: order=0.305___

## Best Lewis Structure

The Lewis structure that is closest to your structure is determined. The hybridization of the atoms in this idealized Lewis structure is given in the table below. Please note that your structure can't be well described by a single Lewis structure, because of extensive delocalization.

### Hybridization in the Best Lewis Structure

1. A antibonding orbital for Si1-Si2 with 1.9862 electrons
__has 49.99% Si 1 character in a sp1.28 hybrid
__has 50.01% Si 2 character in a sp1.28 hybrid

2. A bonding orbital for Si1-Si2 with 1.1651 electrons
__has 50.01% Si 1 character in a sp1.28 hybrid
__has 49.99% Si 2 character in a sp1.28 hybrid

23. A lone pair orbital for Si1 with 1.0700 electrons
__made from a p-pi orbital ( 99.17% p 0.83% d)

24. A lone pair orbital for Si1 with 0.9740 electrons

25. A lone pair orbital for Si1 with 0.6904 electrons
__made from a p-pi orbital ( 98.84% p 1.16% d)

26. A lone pair orbital for Si2 with 1.0700 electrons
__made from a p-pi orbital ( 99.17% p 0.83% d)

27. A lone pair orbital for Si2 with 0.9738 electrons

28. A lone pair orbital for Si2 with 0.6903 electrons
__made from a p-pi orbital ( 98.84% p 1.16% d)

29. A lone pair orbital for Si3 with 0.8059 electrons
__made from a s0.76 p3 hybrid

30. A lone pair orbital for Si3 with 0.5865 electrons
__made from a p-pi orbital ( 98.76% p 1.24% d)

31. A lone pair orbital for Si3 with 0.3099 electrons
__made from a p-pi orbital ( 98.55% p 1.45% d)

32. A lone pair orbital for Si3 with 1.9654 electrons

33. A lone pair orbital for Si4 with 0.8059 electrons
__made from a s0.76 p3 hybrid

34. A lone pair orbital for Si4 with 0.5865 electrons
__made from a p-pi orbital ( 98.76% p 1.24% d)

35. A lone pair orbital for Si4 with 0.3099 electrons
__made from a p-pi orbital ( 98.55% p 1.45% d)

36. A lone pair orbital for Si4 with 1.9654 electrons

-With core pairs on:Si 1 Si 1 Si 1 Si 1 Si 1 Si 2 Si 2 Si 2 Si 2 Si 2 Si 3 Si 3 Si 3 Si 3 Si 3 Si 4 Si 4 Si 4 Si 4 Si 4 -

#### Donor Acceptor Interactions in the Best Lewis Structure

The localized orbitals in your best Lewis structure can interact strongly. A filled bonding or lone pair orbital can act as a donor and an empty or filled bonding, antibonding, or lone pair orbital can act as an acceptor. These interactions can strengthen and weaken bonds. For example, a lone pair donor->antibonding acceptor orbital interaction will weaken the bond associated with the antibonding orbital. Conversly, an interaction with a bonding pair as the acceptor will strengthen the bond. Strong electron delocalization in your best Lewis structure will also show up as donor-acceptor interactions.
Interactions greater than 20 kJ/mol for bonding and lone pair orbitals are listed below.

The interaction of antibonding donor orbital, 1, for Si1-Si2 with the second lone pair acceptor orbital, 24, for Si1 is 384. kJ/mol.

The interaction of antibonding donor orbital, 1, for Si1-Si2 with the second lone pair acceptor orbital, 27, for Si2 is 384. kJ/mol.

The interaction of bonding donor orbital, 2, for Si1-Si2 with the second lone pair acceptor orbital, 24, for Si1 is 3537 kJ/mol.

The interaction of bonding donor orbital, 2, for Si1-Si2 with the second lone pair acceptor orbital, 27, for Si2 is 3533 kJ/mol.

The interaction of antibonding donor orbital, 1, for Si1-Si2 with the second lone pair acceptor orbital, 29, for Si3 is 34.1 kJ/mol.

The interaction of bonding donor orbital, 2, for Si1-Si2 with the third lone pair acceptor orbital, 30, for Si3 is 243. kJ/mol.

The interaction of lone pair donor orbital, 23, for Si1 with the third lone pair acceptor orbital, 30, for Si3 is 947. kJ/mol.

The interaction of the second lone pair donor orbital, 24, for Si1 with the second lone pair acceptor orbital, 29, for Si3 is 1710 kJ/mol.

The interaction of the second lone pair donor orbital, 24, for Si1 with the third lone pair acceptor orbital, 30, for Si3 is 141. kJ/mol.

The interaction of the third lone pair donor orbital, 25, for Si1 with the 4th lone pair acceptor orbital, 31, for Si3 is 498. kJ/mol.

The interaction of lone pair donor orbital, 26, for Si2 with the third lone pair acceptor orbital, 30, for Si3 is 947. kJ/mol.

The interaction of the second lone pair donor orbital, 27, for Si2 with the second lone pair acceptor orbital, 29, for Si3 is 1710 kJ/mol.

The interaction of the second lone pair donor orbital, 27, for Si2 with the third lone pair acceptor orbital, 30, for Si3 is 141. kJ/mol.

The interaction of the third lone pair donor orbital, 28, for Si2 with the 4th lone pair acceptor orbital, 31, for Si3 is 498. kJ/mol.

The interaction of antibonding donor orbital, 1, for Si1-Si2 with the second lone pair acceptor orbital, 33, for Si4 is 34.1 kJ/mol.

The interaction of bonding donor orbital, 2, for Si1-Si2 with the third lone pair acceptor orbital, 34, for Si4 is 243. kJ/mol.

The interaction of lone pair donor orbital, 23, for Si1 with the third lone pair acceptor orbital, 34, for Si4 is 947. kJ/mol.

The interaction of the second lone pair donor orbital, 24, for Si1 with the second lone pair acceptor orbital, 33, for Si4 is 1710 kJ/mol.

The interaction of the second lone pair donor orbital, 24, for Si1 with the third lone pair acceptor orbital, 34, for Si4 is 142. kJ/mol.

The interaction of the third lone pair donor orbital, 25, for Si1 with the 4th lone pair acceptor orbital, 35, for Si4 is 498. kJ/mol.

The interaction of lone pair donor orbital, 26, for Si2 with the third lone pair acceptor orbital, 34, for Si4 is 947. kJ/mol.

The interaction of the second lone pair donor orbital, 27, for Si2 with the second lone pair acceptor orbital, 33, for Si4 is 1710 kJ/mol.

The interaction of the second lone pair donor orbital, 27, for Si2 with the third lone pair acceptor orbital, 34, for Si4 is 141. kJ/mol.

The interaction of the third lone pair donor orbital, 28, for Si2 with the 4th lone pair acceptor orbital, 35, for Si4 is 498. kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the lone pair acceptor orbital, 23, for Si1 is 80.1 kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the second lone pair acceptor orbital, 24, for Si1 is 27.9 kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the lone pair acceptor orbital, 26, for Si2 is 80.0 kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the second lone pair acceptor orbital, 27, for Si2 is 27.9 kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the second lone pair acceptor orbital, 29, for Si3 is 125. kJ/mol.

The interaction of lone pair donor orbital, 32, for Si3 with the second lone pair acceptor orbital, 33, for Si4 is 6.31 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the lone pair acceptor orbital, 23, for Si1 is 80.0 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the second lone pair acceptor orbital, 24, for Si1 is 27.9 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the lone pair acceptor orbital, 26, for Si2 is 80.1 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the second lone pair acceptor orbital, 27, for Si2 is 27.9 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the second lone pair acceptor orbital, 29, for Si3 is 6.31 kJ/mol.

The interaction of lone pair donor orbital, 36, for Si4 with the second lone pair acceptor orbital, 33, for Si4 is 125. kJ/mol.

## Molecular Orbital Energies

The orbital energies are given in eV, where 1 eV=96.49 kJ/mol. Orbitals with very low energy are core 1s orbitals. More antibonding orbitals than you might expect are sometimes listed, because d orbitals are always included for heavy atoms and p orbitals are included for H atoms. Up spins are shown with a ^ and down spins are shown as v.

32 ----- -2.089

31 ----- -3.013

30 ----- -3.245

29 ----- -4.502

28 -^-v- -5.609

27 -^-v- -5.830

26 -^-v- -6.476

25 -^-v- -6.804

24 -^-v- -8.483

23 -^-v- -10.20

22 -^-v- -12.16

21 -^-v- -15.15

20 -^-v- -94.41 19 -^-v- -94.41

18 -^-v- -94.52 17 -^-v- -94.53

16 -^-v- -94.71 15 -^-v- -94.71

14 -^-v- -94.94 13 -^-v- -94.94

12 -^-v- -95.08 11 -^-v- -95.08

10 -^-v- -95.28 9 -^-v- -95.28

8 -^-v- -136.9 7 -^-v- -136.9

6 -^-v- -137.4 5 -^-v- -137.4

4 -^-v- -1772. 3 -^-v- -1772.

2 -^-v- -1773. 1 -^-v- -1773.

## Total Electronic Energy

The total electronic energy is a very large number, so by convention the units are given in atomic units, that is Hartrees (H). One Hartree is 2625.5 kJ/mol. The energy reference is for totally dissociated atoms. In other words, the reference state is a gas consisting of nuclei and electrons all at infinite distance from each other. The electronic energy includes all electric interactions and the kinetic energy of the electrons. This energy does not include translation, rotation, or vibration of the the molecule.

Total electronic energy = -1158.0023023543 Hartrees

* Also check the tetrahedral structure